Some changes, especially early in the games history, were specifically made at the suggestion of members of the forum.
Polls, unless started by a member of staff, are a poor indicator of the route the game is going to take. They often are badly worded and reflect the posters preferences for the game.
Feedback takes place a great deal outside these forums and within them as private messages although it seemed to take place even more in the old forums. (Maybe it's just that they existed longer.)